Page 24 - EVS Class 05

* Oxygen is present in the air around us.
* The ribcage moves outward and upward with the help of the muscles of the
chest while we breathe in.

* The water vapour in the air we breathe out makes the heat coming out of the
hot milk or soup escape faster.
* When we breathe in air through the mouth, the air that enters our lungs is

not clean.

A. Answer the following questions.

1. What happens when we breath in?

2. What happens when we breath out?

3. How can a fire be burnt by blowing air from mouth?
4. Why should we breathe through our nose only?

5. How can blowing air from mouth cools the hot drinks?

B. How does oxygen help us?

Breathe In Breathe Out

C. Label the diagram.

EVS-5
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